Altered miRNA Expression Drives Proliferation of Lymphatic Malformation by Activating Pro-Growth Signaling Cascades

改变的 miRNA 表达通过激活促生长信号级联驱动淋巴畸形的增殖

• 批准号: 10677332
• 负责人: Ravi Sun
• 金额: $ 3.8万
• 依托单位: ARKANSAS CHILDREN'S HOSPITAL RES INST
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-25 至 2027-08-24
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10677332
• 关键词: Anatomy; Angiopoietin-2; Automobile Driving; Biological Assay; Biology; Blood; Blood Vessels; Cell Proliferation; Cell physiology; Complex; Data Set; Dermal; Development; Down-Regulation; Endothelial Cells; Environment; Excision; Exclusion; Functional disorder; Goals; Growth; Growth Factor; Homeostasis; Human; Infiltration; Inflammation; Integrins; Investigation; Laboratories; Lesion; Life; Liposomes; Lymphangiogenesis; Lymphatic; Lymphatic Endothelial Cells; Lymphatic Metastasis; Mediating; Mediator; Mentors; Messenger RNA; MicroRNAs; Molecular; Molecular Biology; Morbidity - disease rate; Multiomic Data; Mutation; Nuclear; Operative Surgical Procedures; Outcome; PIK3CA gene; PIK3CG gene; Pain; Pathogenesis; Pathway interactions; Permeability; Phenotype; Phosphorylation; Physicians; Plasmids; Play; Proliferating; Proteins; Proteomics; Receptor Protein-Tyrosine Kinases; Recurrence; Regulation; Role; Scientist; Sclerotherapy; Signal Transduction; Sirolimus; Small Interfering RNA; Structure; Systems Biology; Testing; Therapeutic; Training; Transfection; Tube; Up-Regulation; Vascular Endothelial Cell; Vascular Permeabilities; Western Blotting; alpelisib; cadherin 5; career; clinical practice; congenital anomaly; differential expression; gain of function; gain of function mutation; immunocytochemistry; improved; inhibitor; insight; knock-down; lymphatic development; lymphatic malformations; lymphatic vessel; mRNA sequencing; migration; multidisciplinary; multiple omics; mutant; new therapeutic target; novel; overexpression; pharmacologic; posttranscriptional; primary lymphedema; protein expression; targeted treatment; therapeutic target; transcription factor; translational medicine

PROJECT SUMMARY/ABSTRACT Lymphatic malformations (LMs) are complex congenital lesions composed of dilated, abnormal lymphatic channels that can result in life-threatening morbidity due to their propensity to enlarge, encroach on nearby anatomical structures, become infected, and cause significant pain and disfigurement. Although somatic, gain- of-function mutations in the PIK3CA gene have been identified in LM endothelial cells (LM-ECs) and are thought to drive aberrant lymphangiogenesis through overactivation of the PI3K/Akt pathway, the mechanisms underlying many phenotypic abnormalities apparent in LMs, such as abnormal vessel formation and permeability, are not fully understood. Considering the significant complications and recurrence rates of traditional treatments for LMs, greater insight into the molecular mechanisms underlying LM pathogenesis is needed to identify novel therapeutic targets and develop improved molecular therapies. Angiopoietin-2 (Ang-2) is a vascular growth factor that plays a critical role in lymphatic development and homeostasis; however, its functions in LMs are unknown. Utilizing a multi-omics approach (miRNA-seq, mRNA-seq, proteomics) to generate a comprehensive network of miRNA-mRNA-protein expression in LM-ECs with gain-of-function PIK3CA mutations compared to normal human dermal lymphatic endothelial cells, we have identified significant downregulation of Ang-2 mRNA and protein in LM-ECs in parallel with significant upregulation of miRNAs in LM-ECs that are predicted post- transcriptional suppressors of Ang-2, yet their function in LM-ECs is unknown. Ang-2 is also downregulated in PIK3CA-mutant blood endothelial cells through Akt-mediated inactivation of its transcription factor, Forkhead box O1. Ang-2 expression can be rescued with PI3K pathway inhibitors; however, this mechanism has not been demonstrated in LMs. Considering the critical role of Ang-2 in lymphatic endothelial cell function, we hypothesize that alternations in Ang-2 expression in LM-ECs drive their abnormal lymphangiogenic phenotype and may be a viable therapeutic target. This hypothesis will be tested with the following specific aims: (1) define the regulatory mechanisms driving differential expression of Ang-2 in LM-ECs and (2) define the impact of aberrant Ang-2 expression on LM-EC proliferation, migration, tube formation, and permeability. This proposal will be the first investigation into the regulation and function of Ang-2 in LMs, potentially uncovering novel mechanisms underlying the pathogenesis of LMs and lymphatic and vascular endothelial cell dysfunction which may improve clinical practice and thus has significant relevance to the field of vascular biology. The overarching goal of this proposal is to identify suitable targets for the development of deliverable, molecular therapeutics. The ACRI Vascular Anomalies Laboratory provides an exceptional training environment, and we have assembled a mentoring team of leaders in vascular anomalies, systems biology, and translational medicine that will facilitate this unique and rigorous training, with the principal goal of preparing for a successful career as an independent physician scientist.

项目摘要/摘要 淋巴畸形（LMS）是复杂的先天性病变，由扩张的异常淋巴 由于其扩大的倾向，附近的倾向，可能导致威胁生命的发病率的渠道 解剖结构，被感染，并引起严重的疼痛和毁容。虽然躯体，但 PIK3CA基因中的功能突变已在LM内皮细胞（LM-EC）中鉴定出来，并被认为 通过过度活化PI3K/AKT途径，驱动异常的淋巴管生成 LMS中明显的许多表型异常，例如异常血管形成和渗透性，不是 完全理解。考虑到LMS传统治疗的显着并发症和复发率， 需要更深入地了解LM发病机理的分子机制，以鉴定新型 治疗靶标并发展改善的分子疗法。血管生成素2（ANG-2）是血管生长因子 这在淋巴发育和稳态中起着至关重要的作用。但是，其在LMS中的功能尚不清楚。 利用多词方法（miRNA-seq，mRNA-seq，蛋白质组学）生成一个综合网络 与正常相比 人真皮淋巴内皮细胞，我们已经确定了Ang-2 mRNA和 LM-EC中的蛋白质与LM-EC中的miRNA显着上调，这是预测的 ANG-2的转录抑制器，但它们在LM-EC中的功能尚不清楚。 Ang-2也被下调 PIK3CA突变的血液内皮细胞通过Akt介导的转录因子的灭活叉子盒 O1。可以使用PI3K途径抑制剂来拯救Ang-2表达；但是，这种机制不是 在LMS中展示。考虑到Ang-2在淋巴内皮细胞功能中的关键作用，我们假设 LM-EC中ANG-2表达的交替驱动其异常淋巴管生成表型，可能是一个 可行的治疗靶标。该假设将以以下特定目的进行检验：（1）定义调节 驱动LM-EC中ANG-2差异表达的机制，（2）定义异常ANG-2的影响 在LM-EC增殖，迁移，管形成和渗透性上的表达。该提议将是第一个 研究ANG-2在LMS中的调节和功能，可能会发现新机制 LMS的发病机理以及淋巴和血管内皮细胞功能障碍的基础，这可能会改善 临床实践，因此与血管生物学领域具有很大的相关性。总体目标 提案是确定适合发展可交付的分子治疗剂的目标。 acri 血管异常实验室提供了特殊的培训环境，我们已经组装了 指导血管异常，系统生物学和转化医学领导者团队，以促进 这种独特而严格的培训，其主要目标是为成功的职业做准备 医师科学家。